compass

Virtual reality systems have been at the forefront of development for several decades. While there are commercial offerings now, it’s interesting to go back in time to when the systems were much more limited. [Colin Ord] recently completed his own VR system, modeled on available systems from 20-30 years ago, which gives us a look inside what those systems would have been like, as well as being built for a very low cost using today’s technology.

The core of this project is a head tracker, which uses two BBC Microbits as they have both the accelerometer and compass needed to achieve the project goals. It is also capable of tracking an item and its position in the virtual space. For this project, [Colin] built everything himself including the electronics and the programming. It also makes use of Google Cardboard to hold the screen, lenses, and sensors all in the headset. All of this keeps the costs down, unlike similar systems when they were first unveiled years ago.

The ground-up approach that this project takes is indeed commendable. Hopefully we can see the code released, and others can build upon this excellent work. You could even use it to take a virtual reality cycling tour of the UK.

If you carry a smartphone around in your pocket, you have a GPS navigation system, a compass, an altimeter, and a very powerful computer at your fingertips. It’s the greatest navigational device ever created. To use this sextant of the modern era you’ve got to look down at a screen. You need to carry a phone around with you. It’s just not natural.

For this entry into the Hackaday Prize, [Vojtech Pavlovsky] has an innovative solution to direction finding that will give you a sixth sense. It’s a headband that turns your temples into the input for a clever way to find yourself around the city or a forest, and it does it with just an Arduino and a few other bits.

The idea behind the Ariadne Headband is to create a haptic navigation system for blind people, runners, bikers, or really anybody. It does this by mounting four vibration motors on a headband, connecting those motors to an Arduino, sniffing data from a digital compass, and getting data over Bluetooth from an Android app.

All of these parts come together to form a new sense — a sense of direction. By simply telling the app to make sure you’re always oriented North, or to guide you along the grid of city streets, this headband becomes an inconspicuous and extraordinarily useful way to get around.

Our recent “Retrotechtacular” feature on an early 1970s dead-reckoning car navigation system stirred a memory of another pre-GPS solution for the question that had vexed the motoring public on road trips into unfamiliar areas for decades: “Where the heck are we?” In an age when the tattered remains of long-outdated paper roadmaps were often the best navigational aid a driver had, the dream of an in-dash scrolling map seemed like something Q would build for James Bond to destroy.

And yet, in the mid-1980s, just such a device was designed and made available to the public. Dubbed Etak, the system was simultaneously far ahead of its time and doomed to failure by the constellation of global positioning satellites being assembled overhead as it was being rolled out. Given the constraints it was operating under, Etak worked very well, and even managed to introduce some of the features of modern GPS that we take for granted, such as searching for services and businesses. Here’s a little bit about how the system came to be and how it worked.

When project inspiration strikes, we’d love to do some quick tests immediately to investigate feasibility. Sadly we’re usually far from our workbench and its collection of sensor modules. This is especially frustrating when the desired sensor is in the smartphone we’re holding, standing near whatever triggered the inspiration. We could download a compass app, or a bubble level app, or something similar to glimpse sensor activity. But if we’re going to download an app, consider Google’s Science Journal app.

It was designed to be an educational resource, turning a smartphone’s sensor array into a pocket laboratory instrument and notebook for students. Fortunately it will work just as well for makers experimenting with project ideas. The exact list of sensors will depend on the specific iOS/Android device, but we can select a sensor and see its output graphed in real-time. This graph can also be recorded into the journal for later analysis.

Science Journal was recently given a promotional push by the band OK Go, as part of their OK Go Sandbox project encouraging students to explore, experiment, and learn. This is right up the alley for OK Go, who has a track record of making music videos that score high on maker appeal. Fans would enjoy their videos explaining behind-the-scene details in the context of math, science, and music.

An interesting side note. Anyone who’s been to Hackaday Superconference or one of the monthly Hackaday LA meetups will likely recognized the venue used in many of the OK Go Sandbox videos. Many of them were filmed at the Supplyframe Design Lab in Pasadena. It’s also nice to see AnnMarie Thomas (Hackaday Prize Judge from 2016 and 2017) collaborated with OK Go for the Sandbox project.

While the Science Journal app has provisions for add-on external sensors, carrying them around would reduce its handy always-available appeal. Not that we’re against pairing smartphones with clever accessories to boost their sensing capabilities: we love them! From trying to turn a smartphone into a Tricorder, to an inexpensive microscope, to exploring serious medical diagnosis, our pocket computers can do it all.

Feel like taking a long walk, but can’t be bothered with carrying your drinks? Have no fear, this “Follow Me” Cooler Bot is here!

Really just a mobile platform with a cooler on top, the robot connects to smartphone via Bluetooth, following it using GPS. Making the platform involves a little woodworking skill, and an aluminium hub with a 3D-printed hub adapter connects the motors to a pair 6″ rubber wheels with a swivel caster mounted at the rear. A pocket in the platform’s base houses the electronics.

The Arduino Uno — via an L298n motor driver — controls two 12V DC, brushed and geared motors mounted with 3D printed brackets, while a Parallax PAM-7Q GPS Module in conjunction with an HMC 5883L compass help the robot keep its bearing. A duo of batteries power the motors and the electronics separately to prevent any malfunctions.

A conventional compass points north (well, to magnetic north, anyway). [Videoschmideo] wanted to make a compass that pointed somewhere specific. In particular, the compass — a wedding gift — was to point to a park where the newlywed couple got engaged. Like waking up in a fresh new Minecraft world, this is their spawn point and now they can always find their way back from the wilderness.

The device uses an Arduino, a GPS module, a compass, and a servo motor. Being a wedding gift, it also needs to meet certain aesthetic sensibilities. The device is in an attractive wooden box and uses stylish brass gears. The gears allow the servo motor to turn more than 360 degrees (and the software limits the rotation to 360 degrees). You can see a video of the device in operation, below.

You’ve probably seen tweezers act as test probes for a multimeter or other instrument. Some electronics testing tweezers even have the multimeter built right in. Tools like these are especially handy for working with surface mount components. [Bweed2] found a probe made by E-Z hook that kept a fixed distance you can set with a thumbwheel. It looked good, but the $70-$80 price tag seemed too much.

Employing hacker ingenuity, he turned to a drafting compass. You know, the tool you use to draw circles. He picked up one for about $10 and then got some cheaper compasses to scavenge their needles (the compass usually only has one needle since the other side holds a pencil). The result was a useful set of adjustable probes.

Once you have the idea, it is a pretty simple project. Immobilize the knee of the compass with glue, connect some wires and–for extra points–add some red and black heat shrink to make it pretty.

Want to make a more classic SMD tweezer? Here’s one we’ve covered before. If you’d rather use your feet and your ears with your probes, you might be interested in these.